The sudden appearance of red spots on the body, not itchy, consider the following cases: 1, dermatitis, skin stimulated by external stimuli resulting in skin stress reactions, with Bactrim ointment or Sanjiu dermatitis ointment rub the affected area, oral loratadine tablets, drink more water, eat more fresh vegetables, fruits, do not eat spicy food. 2, upper respiratory tract infection or tonsillitis after the sudden appearance of red spots on the body, covered with scales consider Let the patient rest in bed, high protein diet, eat more food with high vitamin C content and keep away from allergens.